add_library(calc STATIC basic.cpp)
target_include_directories(calc INTERFACE
  "$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>"
  "$<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>"
)
set_target_properties(calc PROPERTIES
  PUBLIC_HEADER "include/calc/basic.h"
)

include(GNUInstallDirs)
install(TARGETS calc EXPORT CalcTargets ARCHIVE FILE_SET HEADERS)
install(EXPORT CalcTargets
  DESTINATION ${CMAKE_INSTALL_LIBDIR}/calc/cmake
  NAMESPACE Calc::
)